I keep mine is separate pens, but I am running out of pens.
Yeah well, I only have one brooder and one holding pen and multiple varieties of chicks. Of course my brooder is 4'x4' and easily holds lots of chicks. I need to get it cleaned and ready for the next hatch which is due Monday.
I wasn't happy yesterday since I had to fire up the lawnmower for the first time as the grass is getting out of control. It was just last Sunday that it had 2 1/2" of snow on it.